12-Ch RS485 Modbus RTU Relay Module DC 12/24V DIN Rail
12-Ch RS485 Modbus RTU Relay Module DC 12/24V DIN Rail
12-Channel DC 12/24V NPN Digital I/O RS485 Relay Module with Modbus RTU – DIN35 Rail Mount
Take full control of your automation projects with this professional-grade 12-Channel RS485 Relay Module. Designed for industrial and hobbyist machine control applications including PLC systems and PTZ camera setups, this module delivers rock-solid switching performance via Modbus RTU communication over RS485. Available in DC 12V and DC 24V versions, it mounts neatly on a DIN35/C45 rail inside its included UM72 green flame-retardant enclosure.
Made in China.
Key Features
- 12 Photoelectric Isolation Input Ports – NPN low-level active; input/output relationship configurable as associated (default) or non-associated via command
- 7 Flexible Control Commands – Open, Close, Momentary, Self-Locking, Interlock, Delay (up to 255 seconds), and Two-Channel Interlock
- Modbus RTU Protocol – Supports function codes 03, 06, and 16; compatible with HyperTerminal and Modbus Poll software
- Multi-Device Network – Connect up to 64 devices in parallel on a single RS485 bus
- Selectable Baud Rate – Jumper-configurable: 2400 / 4800 / 9600 (default) / 19200 BPS
- Heavy-Duty Relay Contacts – Rated at 10A / 250VAC, 10A / 125VAC, 10A / 30VDC
- DIN35 & C45 Rail Compatible – Ships with UM72 model enclosure (flame-retardant V0 grade) for clean panel installation
- Low Standby Draw – As low as 14 mA with all relays closed; scales predictably with active relays
Specifications
| Input Voltage | DC 12V or DC 24V (version-dependent) |
| Channels | 12 relay output / 12 digital input |
| Communication | UART / RS485, Modbus RTU |
| Function Codes | 03, 06, 16 |
| Max Delay | 255 seconds |
| Max Parallel Devices | 64 |
| Baud Rates | 2400 / 4800 / 9600 / 19200 BPS |
| Max Load | 10A / 250VAC; 10A / 30VDC |
| PCB Size | 180 × 72 × 20 mm |
| With DIN Rail Box | 184 × 88 × 42 mm |
| PCB Weight | 190 g |
| With Box Weight | 318 g |
| Enclosure Model | UM72, Green, Flame-Retardant V0 |
| Rail Type | DIN35 / C45 |
| EU LVD Compliance | Below 50VAC / 75VDC |
Ideal Applications
- PLC machine control panels
- PTZ camera and surveillance systems
- Industrial automation and building management
- Access control and door locking systems
- Smart home and HVAC switching logic
Package Includes
- 1× 12-Channel RS485 Relay Module (with DIN Rail Box)
Note: Due to lighting and screen variations, actual product color may differ slightly from images. Please allow 1–10 mm tolerance due to manual measurement.
For more on industrial relay and automation standards, refer to the NIST Manufacturing Standards resource. Additional safety guidance for low-voltage industrial equipment is available from OSHA Electrical Safety.
Frequently Asked Questions
Q: What communication protocol does this 12-channel relay module use?
A: This relay module communicates via RS485 using the Modbus RTU protocol, supporting function codes 03 (read), 06 (write single register), and 16 (write multiple registers). It is compatible with standard tools such as HyperTerminal and Modbus Poll software, making integration straightforward for PLC and automation engineers.
Q: Can I connect multiple relay modules on the same RS485 bus?
A: Yes. The module supports up to 64 devices connected in parallel on a single RS485 bus, making it ideal for large-scale automation and machine control installations where many switching points are required.
Q: What is the difference between the 12V and 24V versions?
A: Both versions offer identical relay channel counts, commands, and communication features. The only difference is the input supply voltage — choose DC 12V if your control panel runs on a 12V supply, or DC 24V for 24V industrial systems. The relay contact ratings (10A / 250VAC) remain the same across both versions.
Q: Does the module come with a DIN rail enclosure?
A: Yes. Each module ships with a UM72 green flame-retardant V0-rated DIN rail enclosure that is compatible with standard DIN35 and C45 rails. The assembled unit measures 184 × 88 × 42 mm and weighs 318 g.